This invention relates to devices for controlling electrical apparatus and more particularly to devices of his kind which are disposed at the face of an electronic display screen which displays changeable information pertinent to operation of the control device.
Electrical control devices such as switches, potentiometers, faders, joysticks and the like typically require graphics which mark the settings of the control and/or which convey other information useful to the operator of the device. Traditionally such graphics have been permanent markings imprinted at locations adjacent, to or near the operator manipulated member of the control device. This may not provide the operator with all of the information that might be useful as only a limited amount of space is available for the permanent markings. Unchangeable imprinted graphics also cause difficulties in the case of a multi-purpose control device which serves different purposes during different modes of operation of the controlled apparatus. Graphics which are appropriate for one mode of operation may be irrelevant to another mode of operation.
These problems have heretofore been addressed by disposing electrical control devices in front of an electronic display screen. The screen can display changing graphics which convey more information than is possible with a single set of permanently imprinted markings and/or which change when the control device is used to control different modes of operation of an electrical apparatus. Prior U.S. Pat. No. 5,572,239; U.S. Pat. No. 5,805,146 and U.S. Pat. No. 5,936,613 disclose examples of control devices having integrated display screens of this kind.
Control devices of this type have a movable member, such as a turnable or slidable knob or cap, a switch button or a joystick for example, that is manipulated by the operator to change the setting of the control. The operator""s manipulations of the movable member are detected by motion sensing means which then transmit an appropriate control signal to the controlled apparatus. The motion sensing means may be of a variety of different types. The motion sensing means may variously include rotary or linear potentiometers or variable resistances, photoelectric motion sensors or magnetic sensors which utilize the Hall effect, among other examples.
Controls of the fader or linear potentiometer type have a movable cap which is slid along a linear path to vary a control signal. In traditional controls of this type which have permanently imprinted graphics the movable cap is mounted on a stem which extends into the underlying control panel or the like through a thin slot. Components which produce a control signal in response to movement of the cap are situated behind the panel. It is possible to provide a thin slot in an electronic display screen, where the control is to be disposed at the face of such a screen, but this requires that the screen have a specialized internal construction which can increase manufacturing cost. This can be avoided by providing a track at the front of the display screen which supports the movable cap and stem. Heretofore, electronic components which detect movement of the cap and which produce the variable, control signal in response to such movement have been disposed within the track. Inclusion of such components requires that the track be bulkier than would otherwise be the case. It is more comfortable to operators of the control and more attractive if the track is of minimal size and as unobtrusive as possible.
The present invention is directed to overcoming one or more of the problems discussed above.
In a first aspect this invention provides a control, device for producing control signals for electrical apparatus. The control device has a movable member that is slidable along a track and has control signal producing components which vary the control signal in response to movement of the movable member. The movable member and track are disposed at least in part at the face of an electronic display screen which displays pertinent to operation of the control device. At least a portion of the control signal producing components are at an off screen location which is away from the face of the display screen. The movable member is linked to the control signal producing components by a slidable tongue which extends along the track from the movable member to the off screen location.
In another aspect of the invention, a control device for producing control signals for electrical apparatus is disposed in front of the image display area of an electronic display screen that displays graphics pertinent to operation of the control device, the control device being fastened to the display screen by a snap, engagement.
In another aspect of the invention, a control device for producing control signals for electrical apparatus is disposed in front of the image display area of an electronic display screen that displays graphics pertinent to operation of the control device The control device has a linear track which extends along the display screen and a cap which is slidable along the track to vary the electrical control signal. The cap is supported by a support post which travels along the track with the cap, the cap being fastened to the support post by a disengageable snap engagement.
In another aspect of the invention a control device for producing control signals for electrical apparatus is disposed in front of the image display area of an electronic display screen that displays graphics pertinent to operation of the control device. The control device has a base portion affixed to the display screen at the image display area thereof. The device further includes a carrier plate disposed within the base portion and a knob which is turnable relative to the base portion, the turnable knob being fastened to the carrier plate by a snap engagement.
In another aspect of the invention, a control device for producing control signals for electrical apparatus has a fixed base and a component which is turned by a knob to vary a control signal. Rotary motion of the knob is transferred to the component by a turnable intermediate member which is constrained to rotate with the knob and which rotates the component. The knob is disengageable from the base member and the intermediate member to enable replacement of the knob with another knob.
In another aspect of the invention a control device for producing control signals for electrical apparatus is disposed at the front of an electronic image display screen which displays changeable graphics that are pertinent to operation of the control device. The control device has a fixed base and a knob thereon which is turned about an axis of rotation that extends at right angles to the display screen to vary,an electrical control signal. The control device further has a cylindrical member disposed in coaxial relationship with the axis of rotation and which turns about the axis of rotation with the knob. The cylindrical member has angular position identifying coding thereon. At least one coding sensor is positioned to read successive portions of the coding as the cylindrical member turns about the axis of rotation.
In another aspect of the invention a control device for an electrical circuit has a knob which is turnable to any of a plurality of different angular orientations to change an electrical condition in the circuit. The knob is disposed in front of an electronic image display device which has an image display area at which changeable images are displayed and at least a portion of the knob at a location which overlays the image display area of the image display device. A control signal producing circuit at that location produces an electrical signal that varies in response to turning of the knob. An infrared transmitter in the control device transmits the signal in the form of modulated infrared energy. A signal receiving circuit situated away from the image display area of the image display device includes an infrared receiver which converts the infrared signal back into an electrical signal.
In another aspect of the invention a control device for an electrical circuit has a knob which is turnable to any of a of a plurality different angular orientations to change an electrical condition in the circuit. The knob is disposed in front of an electronic image display device which has an image display area at which changeable images are displayed and at least a portion of the knob is at a location which overlays the image display area of the image display device. A control signal producing circuit at that location produces an electrical signal that varies in response to turning of the knob. An ultrasonic transmitter in the control device transmits the signal in ultrasonic form. A signal receiving circuit situated away from the image display area of the image display device includes an ultrasonic receiver which converts the ultrasonic signal back into an electrical signal.
In another aspect of the invention a control device for an electrical circuit has a cap which is slidable along a track to any of a plurality of different positions to change an electrical condition in the circuit. The cap and track are disposed in front of an electronic image display device which has an image display area act which changeable images are displayed. At least portions of the cap and track overlay the image display area of the image display device. A signal producing circuit is disposed within at least one of the cap and the track and produces an electrical signal that varies in response to movement of the cap along the track. A signal transmitter transmits the signal outward from the control device. A receiving circuit situated away from the image display area of the image display device converts the transmitted signal back into an electrical signal.
In another aspect of the invention a control device for an electrical circuit is a joystick having a member which is deflectable in lateral directions to change an electrical condition in the circuit. The joystick is disposed in front of an electronic image display device which has an image display area at which changeable images are displayed. At least a portion of the joystick overlays the image display area of the image display device. A signal producing circuit within the joystick produces an electrical signal that varies in response to deflections of the deflectable member. A signal transmitter transmits the signal outward from the joystick. A signal receiving circuit situated away from the image display area of the image display device converts the transmitted signal back into an electrical signal.
In one aspects the invention provides an improved control device of the kind in which a member is slidable along a track to vary a control signal and wherein the track is at the face of an electronic display screen which can display changeable graphics pertaining operation of the control. A slidable tongue extends along the track to link the slidable member with control signal producing electronic components which are at a location that is away from the face of the screen. The track may then be desirably compact and unobtrusive to the operator as some or all of the electronic components are not contained within the track. In another aspect the invention enables easy replacement of control devices and components of the devices at a display screen and movement of the devices between different locations by use of snap engagements. In another aspect the invention provides an improved construction for control devices at a display screen which have rotatable coded elements for sensing the angular orientation of a turnable member. In still another aspect the invention, control signals produced by a control device at the face of a display screen are transmitted to an off screen location without the use of electrical conductors on the screen.